-LRB- CNN -RRB- -- Sean Penn and Gus Van Sant have a proposition for us : a biopic dedicated to the memory of San Francisco activist and City Supervisor Harvey Milk , the first openly gay man to be elected to public office in California , who was murdered by a fellow supervisor in 1978 .

Sean Penn plays San Francisco City Supervisor Harvey Milk in `` Milk , '' directed by Gus Van Sant .

The subject may be a tricky sell , but the timing feels right -- a few weeks late to save Californians ' same-sex marriage rights , admittedly , but the need to keep on fighting through adversity may be Milk 's most important legacy .

And `` Milk '' is a powerful movie that will stir more than a few hearts and minds .

An audiotape Milk records `` just in case '' is screenwriter Dustin Lance Black 's convenient structuring device , foregrounding the story 's tragic outcome and allowing Milk to narrate his own life story .

In this telling , it 's a life that begins at 40 -- when he picks up Scott -LRB- James Franco -RRB- , falls in love , comes out and drops out . The year is 1970 , and San Francisco beckons . Their Castro Street camera store soon becomes a focal point for the booming gay community , and it 's not long before Milk makes the first of several unsuccessful runs for district supervisor .

Civic elections might seem like small beer , but the persecution that compelled Milk to run for office is no trivial matter . The gay rights movement 's most critical accomplishment , the film suggests , is how it liberated gays to be themselves .

As Milk tries to explain to his heterosexual colleague Dan White -LRB- Josh Brolin -RRB- , this is n't about principles , it 's about people 's lives -- three of his lovers had threatened suicide . One of them , Jack Lira -LRB- Diego Luna -RRB- , goes through with it . The political ca n't get more personal than that . Ironically , the devoutly `` normal '' White is the one who is truly messed up .

Here 's another irony : To earn the recognition and validation of the voters , Milk has to shed his reborn hippie uniform and ponytail , put on a suit and get a haircut . Making the same calculation , director Gus Van Sant has axed the long takes and experimentalism that made `` Elephant '' and `` Paranoid Park '' arresting but decidedly marginal experiences and turned in his most conventional movie since `` Finding Forrester . '' In other words , he 's playing it straight this time .

The strategy is sound ; the execution , nearly flawless . Van Sant captures the time and the place with unobtrusive precision , seamlessly mixing in reams of archival news reports . -LRB- She may not know it , but Anita Bryant has a co-starring role in this movie . -RRB- iReport.com : Share your reviews of ` Milk '

Penn is studied and thoughtful , impassioned and immediately sympathetic as Milk . It 's easy to see how he attracts so much support -- and how his drive and commitment do n't leave enough time for a `` real '' life . When Penn smiles , there 's always pain there -- it 's almost a wince -- and he smiles a lot here .

`` Milk '' may be a little too homogenized for some tastes . Like `` Philadelphia '' and `` Brokeback Mountain , '' it 's careful how it advances its agenda -LRB- and it does have one -RRB- .

But it 's not just a single-issue movie . In its conviction that `` change '' is n't effected through rhetoric alone , but through the hard slog of campaign work , persuasion , inspiration , inclusion and good old , bad old politicking , `` Milk '' says something about how progress is achieved in America . In that respect , it evokes the best aspirations of the country -- and , for that matter , of filmmaking .

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`` Milk '' is a biography of openly gay San Francisco City Supervisor Harvey Milk

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Film works both as a subtle message film and as well-made movie

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Sean Penn gives excellent performance as Milk